The Build Divers see Freddie on the pop up video screen, and Kazami pushes the button to accept the mission. They are then transported to the temple in Eldora, where Freddie cries tears of joy and hugs Kazami. They head outside and see their Gunpla slowly materializing, and Freddie comments that it’s taking longer than usual. May asks about the glowing particles forming the Gunpla, and Freddie explains that it’s special shining sand found only in the ruins. He adds that when he summons them, the shining sand gathers to form not just their Gunpla, but also their bodies. The process suddenly stops, fully materializing only the Core Gundam II, Mobile Doll May, the Valkylander sword and shield and the Justice Knight‘s Circle shield. May notes that there seems to be a shortage of sand, and Freddie wonders what they should do. Muran drives a car through the desert and spots the Build Divers in the air. In the village, Maiya and the children are surprised when they see the Core Flyer and Mobile Doll May fly in and land. Asha, Towana and Hulun run over to greet the Build Divers and thank Freddie for bringing them back. Tonoi thanks the Build Divers for returning and comments that they still haven’t been able to recover from the Moon attack. Hiroto says they weren’t able to prevent it, but Tonoi declares that the Build Divers are their only hope. Jiric explains that some of them were saved on the day of the attack because they were able to hide behind the Earthree Gundam shield that Hiroto left behind. Muran tries to enter the room, but the children think he’s a suspicious stranger and bite his leg, arm and tail. Muran starts to say something, but May finishes his thought that he was worried they had betrayed everyone just like Masaki did. Muran asks if they know Masaki, and Hiroto answers that they’ve fought the Gundam Seltsam multiple times, most recently in space. Muran explains that the pendant he gave them was a key meant to be used by Masaki, but instead he became an enemy at the key’s destination. Hiroto notes sadly that Muran trusted them and things turned out this way, but Muran counters that given the enemy’s power, this would’ve happened regardless of who used the key. May asks what happened to the Resistance, and Muran explains that most of them were gathered at Seguri. He adds that One-eye activity has increased since then and asks if the Build Divers are going to help again. Freddie declares that the Build Divers will fight alongside them, and May states that this is why they came back. Hiroto says they need to know more about Eldora, and Muran offers whatever help he can. Hiroto wants to return to the One-Eyes base in space because he thinks that’s the only way to resolve things. May believes that would be difficult without all their Gunpla, and Freddie thinks the shining sand was blown away by the impact from the lunar attack. Trying to gather up the scattered sand is unfeasible, so Muran suggests using other ruins instead. He explains that the Resistance identified three other ruins, and while he doesn’t know if they’re usable, it’s worth investigating. The team decides to divide up, with Hiroto and May heading for one site near villages attacked by One-Eyes, Kazami driving on his own to another site, and Parviz and Freddie joining Muran on the path to Milaag Mountain, home of the sacred beast Cuadorn. Parviz asks if sacred beasts really exist, and Freddie explains that they’re divine beings who watch over them from space. Hiroto tells Muran that he doesn’t think Masaki intended to betray the villagers. The team then splits up, and Maiya drives the car for Kazami since he doesn’t know how to drive.
May asks Hiroto why he said what he did to Muran when they don’t have any proof, and Hiroto answers that while Muran was hurt by Masaki’s action, he sensed that Muran was also concerned about Masaki. May asks if this is what human kindness is, and Hiroto wonders why Alus hasn’t attacked Eldora again. Maiya drives recklessly through the forest and takes them to a river. Kazami starts to tell Maiya about the reason for Alus’ attack, but she can’t hear him over all the noise. Freddie asks if Cuadorn will really meet with them, and Muran says there’s no way to know unless they try. Parviz asks Freddie why he’s giving a lantern to Cuadorn, and Freddie explains that the lanterns from the Space Crossing festival are sent to Cuadorn, who fills the lanterns with the souls of the dead and sends them to space. Freddie is bringing the lantern to ask Cuadorn to send Jed’s soul back to space. Hiroto and May are attacked by three Eldora Windams and have trouble fighting them with smaller units. A Windam attacks May with an axe, and she uses Kazami’s Circle shield to block. Hiroto fires his core spray gun to destroy the Windam’s axe, and he comments that their machines aren’t enough to keep up with the performance of the enemies. May kicks the Circle shield at a Windam to destroy its rifle, and Hiroto destroys another with the Valkylander sword. He then tosses the sword to May, which she uses to destroy a Windam. With one enemy left, Hiroto performs a core change to Core Flyer mode and takes to the air. The Windam gives chase as he ascends, and Hiroto cuts his engine to let it pass him before he opens fire. The damaged Windam then crashes into the ground and explodes. Hiroto goes on foot to study one of the destroyed Windams, and a Guard Eye breaks out from its interior. The Guard Eye targets Hiroto, but May kicks it away and destroys it with her pistol. Hiroto is surprised to see this is the true form of the One-Eyes. Muran drives the car to Tayom Peak and tells Freddie and Parviz that Milaag is technically not a mountain, but rather a floating temple that moves through the sky. He adds that the strong seasonal updraft at Tayom Peak will take them up to Milaag. Hiroto and May reach the ruins and find them in even worse shape, with damaged summoning pedestals and little shining sand. They pick up two Windams and a Hover Brute on sensors and decide to hide and let them pass. The three enemies come near the ruins, but then change course. May thinks their movements were odd, and Hiroto recalls an earlier incident and has an idea. Muran unloads the parts for a hot air balloon from the car and tells Freddie and Parviz that he wants them to fly up to Milaag and meet Cuadorn. Elsewhere, Masaki destroys several Eldora Army units that set a crop field ablaze and then howls in pain.
The previous two episodes, each set on Earth and Eldora, ended at the same point in time, so now the story can finally advance. The Build Divers are back in Eldora for the first time since discovering that it wasn’t part of GBN, so things like Kazami’s complaints about NPD dialogue are thankfully out the window. The situation is also different in that their Gunpla can’t fully manifest in the temple Freddie uses to summon them due to lack of shining sand, which certainly sounds to me like nanomachines. The combination of (potential) nanomachines and the Resistance uncovering and using lost technology both seem like nods to Turn A Gundam. Since we’re now past the halfway point, it’s time for Hiroto’s mid-series upgrade, which sees the Core Gundam II being capable of transforming into a Core Flyer. They’re not seen in this episode, but obviously there are also new armors coming for the outer planets of the solar system. Although the previous episode was a misstep, the story seems to be back on track now.